Fuel Rail - Recommended Replacement Method
850/S70/V70/C701995-
Section
2
Group
23
No.
0018
Year
98
Month
09
Vehicles involved:
B52XXS, B52X4T
23-0018; Fuel delivery system ; 98/09
Background:
The following method is recommended when replacing fuel rail to ensure correct installation. This is a supplement to service manuals, LH/EZ, Fenix, Motronic 4.3 and Motronic 4.4.
Materials:
Mounting screws 2 969339-1
Fuel hose 1 9155869-2
O-ring. 1 968007-5
The 0-ring P/N 968007 MUST be replaced when the system has been disassembled.
Replacing fuel rail, delivery/return lines, injectors and pressure regulator
Corrective action when replacing fuel rail, delivery/return lines injectors and pressure regulator
Draining the fuel system 1
Drain fuel system See other manual: Draining fuel injection system Section 2 (23, 28) TP 2308202.
Replacing fuel rail 2
Remove:
- cover over fuel rail.
- injector connectors.
- 2 fuel lines clamps to prevent pipes bending, see illustration.
Note!
Carefully remove both retaining clamps for the fuel pipes to prevent fuel spillage when the fuel rail is removed.
Remove:
Note!
Ensure that the pipe surface is not damaged when removing the return hose.
- pressure regulator vacuum hose.
(The above text listed under Remove:, applies only to cars with fuel return system).
- fuel rail mounting screws.
Carefully work off fuel rail.
Disconnect the fuel rail from the fuel line by twisting it through 90° and carefully pulling if away from the fuel line.
Place paper under the connection to absorb any fuel leakage.
Note!
Do not pry out claw connection using a fool. Twist pipe according to the above text.
Replacing nozzles and pressure regulator 3
Model year - 1997.
See other manual: Injector valve, replacement Section 2 (23, 28). Procedures TA1-TA5, TB1-TB3.
TP 2301201
Disconnecting injectors and pressure regulator 4
Model year 1997-.
Remove:
- screws holding mounting rail to fuel rail.
- mounting rail.
- pressure regulator for cars with fuel return system.
- injectors.
Note!
Handle injectors carefully to avoid damage to nozzles and needles.
Installing injectors 5
Install nozzles and pressure regulator in the new fuel rail. Lubricate nozzle 0-rings with petroleum jelly.
Locate mounting rail. The injectors may need to be pulled away from the fuel rail a few millimeters to install the rail.
Install mounting rail to fuel rail. (Tightening torque 6 Nm (53 in. lbs)).
Note!
The nozzles have two channels at the top against the fuel rail. The mounting rail must sit in the uppermost channel.
Installing fuel rail 6
Install a new O-ring on the pressure pipe.
Note!
Lubricate nipple O-ring with petroleum jelly.
Carefully press in pipe and nipple into fuel rail.
Turn fuel rail 90° and ensure that the lock facing on the nipple is in the correct position in the fuel rail.
Caution!
Take care not to bend lock facing.
Secure delivery line with tool no. 999 5620. See illustration
Lubricate injector O-rings with petroleum jelly.
Install fuel rail on intake manifold. Make sure that the injectors locate correctly.
Screw fuel rail into place. Use new screws. (Tightening torque 10 Nm (7.3 ft. lbs)).
Remove tool securing nipple.
Install:
- vacuum hose on pressure regulator.
Note!
New return hose.
(The above two points apply only to cars with return fuel system)
- fuel line clamps
- injector connectors. Check that that each connector has a rubber seal.
- covers over fuel rail and throttle pulley.
That there is no leakage.
Replacing return line 7
Draining the fuel system
Drain fuel system See other manual: Draining fuel injection system Section 2 (23, 28) TP 2308032.
Remove:
- the 2 fuel line clamps. See illustration.
- the return line hose mounting on the pressure regulator which is located in the fuel rail.
- the return line joint on the hose under the car. Install the new return line in reverse order.
Note!
New return hose.
Removing the rail with injectors 8
Remove:
- fuel rail cover.
- injector connectors.
- 2 fuel lines clamps to prevent pipes bending, see illustration.
Note!
Carefully remove both retaining clamps for the fuel pipes to prevent fuel spillage when the fuel rail is removed.
Install:
- holder 999 5533 on injectors.
Press in the holders so that they are in good contact with injectors.
Screw down adjustment screw so that the contact plate is in contact with the fuel rail, turn the screw another half turn.
The illustration shows holder 999 5620 for securing the nipple which is positioned closest to the fuel delivery line (late version fuel rail).
Remove:
- vacuum hose from pressure regulator.
(The above point applies only to cars with return fuel system)
- screws holding fuel rail.
Lift up fuel rail and carefully turn upwards. Check that the pipe does not bend and hook the center injector behind the gutter sealing Strip.
Note!
Handle injectors carefully to avoid damage to nozzles and needles. Retain any damping rubbers on the intake manifold.
Replacing delivery lines 9
Draining the fuel system
Drain fuel system See other manual: Draining fuel injection system Section 2 (23, 28) TP 2308202.
Removing delivery lines
Remove:
- cover over fuel rail.
- injector connectors.
- 2 fuel lines clamps to prevent pipes bending, see Illustration.
Note!
Carefully remove both retaining clamps for the fuel pipes to prevent fuel spillage when the fuel rail is removed.
Remove:
- the return pipe at the pressure regulator.
- pressure regulator vacuum hose.
(The above two points apply only to cars with return fuel system)
- fuel rail mounting screws.
Carefully work off fuel rail.
Disconnect the fuel rail from the fuel line by twisting it through 90° and carefully pulling it away from the fuel line. Place paper under the connection to absorb any fuel leakage.
Remove:
- delivery line from the delivery line under the car at the sub-frame. The delivery line is marked with yellow tape.
Installing delivery lines
Install a new O-ring on the delivery line.
Carefully press in pipe and nipple into fuel rail.
Note!
Lubricate nipple 0-ring with petroleum jelly.
Turn fuel rail 90° and ensure that the lock facing on the nipple is in the correct position in the fuel rail. Take care not to bend lock facing.
Secure delivery line with tool no. 999 5620.
Lubricate injector O-rings with petroleum jelly.
Screw fuel rail into place.
Use new screws. (Tightening torque 10 Nm (7.3 ft. lbs)).
Remove tool no. 999 5620 securing nipple.
Install:
- vacuum hose on pressure regulator.
Note!
New return line.
(The above two points apply only to cars with return fuel system)
- fuel line clamps
- injector connectors. Check that each connector has a rubber seal.
- covers over fuel rail and throttle pulley.
WARRANTY STATEMENT: Warranty may be submitted under the new car factory warranty when there is a documented customer complaint, using claim type 01.
Operation No. Labor description Time allowance
23712-2 Replace fuel rail 0.6 hr
23415-3 Replace front delivery line 0.2 hr
23418-3 Replace front return line 0.1 hr